WASHINGTON (Reuters) - A U.S. Senate committee approved the nomination of President Donald Trump's choice for secretary of state, Mike Pompeo, on Monday after a Republican senator who had been opposed threw his support behind the CIA director in the face of party pressure.

The Senate Foreign Relations Committee approved the nomination on a party-line vote, with all 11 Republicans backing him, nine Democrats opposed and one Democrat, Chris Coons, voting "present" because one Republican was at a funeral out of town.

Majority Leader Mitch McConnell said there were enough votes in the full Senate to confirm Pompeo this week. That would allow Pompeo to attend a NATO summit on Friday.

Pompeo became one of Trump's closest advisers during his 15 months as CIA director. He most recently has been deeply involved in preparations for Trump's summit with North Korean leader Kim Jong Un, including meeting with him three weeks ago.

While many Democrats consider Pompeo too hawkish and worry about past harsh statements on homosexuality and Islam, he has the support of at least three Democratic senators not on the committee who are running for re-election in states Trump won easily in 2016. That all but assures Pompeo will be confirmed.

"I do not believe Director Pompeo is someone who will always prioritize diplomacy over conflict, particularly in the context of the aggressive foreign policy voices growing around him," said Senator Robert Menendez, the top Democrat on the Foreign Relations Committee, citing Pompeo's past openness to regime change in North Korea and Iran.

No Republican besides Senator Rand Paul, who changed his vote on Monday, had announced opposition.

Paul's late switch meant Pompeo avoided the embarrassment of being the first nominee for secretary of state to fail to secure the committee's endorsement since it began considering them in the late 19th century.

That would have weakened Pompeo's reputation internationally and cast a cloud over Trump's push to overhaul his national security team after firing Secretary of State Rex Tillerson and replacing his national security adviser, H.R. McMaster, with John Bolton, also known as a hawk.

The White House and Republican Party had thrown their weight behind the nomination, with unceasing attacks on Democrats for opposing Trump's pick.

Paul had opposed Pompeo for weeks, holding a news conference to announce his opposition to him, as well as Trump's pick to replace him at the CIA, Deputy CIA Director Gina Haspel.

Haspel, whose Senate confirmation hearing is next month, also faces a tough confirmation fight. Democrats, and some Republicans, are concerned about her links to the CIA's past use of "harsh interrogation techniques," widely seen as torture.

Paul has repeatedly threatened opposition on policy positions staked out by Trump, before changing his mind at the last minute. Trump recently predicted he would come around again on Pompeo, calling Paul "a good man" who has "never let us down."